<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
        <script src="../js/react.development.js"></script>
    <script src="../js/react-dom.development.js"></script>
    <script src="../js/babel.min.js"></script>
</head>
<body>
    <div id="root"></div>

    <script type="text/babel">
        class Hello extends  React.Component{

            componentDidMount(){
                console.log('componentDidMount')
            }
            componentWillUnmount(){
	            console.log('componentDidMount');
            }
            render(){
                return(
                <h1> hello</h1>
                )
            }
        }

        ReactDOM.render(<Hello/>, document.getElementById('root'));

        setTimeout(()=>{
            ReactDOM.render(
                <h1>hahah</h1>,document.getElementById('root'));
        }, 5000);
    </script>
</body>
</html>